The cryopreservation (freezing) process is the preserving of a cell, tissue or a full organism at temperatures below zero degrees Celsius under suitable conditions and in the presence of chemicals. It is aimed to stop enzymatic and chemical reactions at lower temperatures and store the materials without getting damaged further. In order to stop all biological activity and realize the most effective biological freezing process, liquid nitrogen (−196° C.) and vapor are preferred. There are cryoprotectants which are developed for this purpose and which protect the material that will be frozen against freeze-thaw stress. The most important detrimental effect of the freezing process is accumulation of the water in the living system in intercellular and intracellular areas which form of ice crystals due to decreasing of the temperature (Carpenter, and Hansen, 1992). The freezing and thawing process is performed by slowly decreasing the temperature which stops biological activities and then rapidly warming and transferring into a normal culture medium. One of the events which occur during this application and which is known to have detrimental effects is the “solution effect” (medium effect). This effect is caused by the metabolites accumulating in the small amount of liquid medium remaining after ice formation. Following the slow freezing process, the cells are exposed to these metabolites for a prolonged period of time (Stachecki et al., 1998). Another detrimental effect is the intracellular liquid flowing out of the cell and forming ice crystals in the intercellular area as a consequence of slow freezing application. Chemicals such as glycerol, dimethyl sulfoxide (Me2SO) and 1,2 propandiol (PrOH) are used during freezing process and they replace water enabling it to flow out of the cell. This is used for eliminating the detrimental effects of the freezing process (Stachecki et al., 1998). As much as the freezing process should be performed slowly, thawing process should be performed rapidly. The rapidly thawed cells should be quickly transferred to a healthy culture medium in order to get rid of the toxic effects of the chemicals used in the freezing process (Buchanan et al., 2004). In this case, freezing media and methods which are non-toxic, can increase cell viability, and can provide effective protection are needed. An effective cell cryopreservation process is needed for embryos, sperm and egg cells and important cell lines such as stem cells. Storage of stem cells and particularly of mesenchymal stem cells, and establishing stem cell banks are necessary for therapeutic applications (Woods et al., 2009). Storage of the stem cells under suitable conditions is extremely important to be able to use them effectively in therapy. Long-term freezing and storage is required for the cells to maintain their multipotent properties, to be stocked at large numbers and to be easily transported (Gonda et al., 2008). Boron is a trace element which is known to be important particularly in plants. In mammalian system, it forms cell membrane glycoproteins and diester borate complexes and functions as a redox regulator and also affects membrane structure and function (Goldbach et al., 2007).
European patent document no. EP0813361B1 relates to a medium used for freezing the cells, particularly the erythroid progenitor cells in blood.
United States patent document no. US20130059381A1 relates to a cell cryopreservation solution that can be used for non-programmed cell cryopreservation.